OPINION:
Soon after Sir David Carruthers took over as head of the Independent Police Conduct Authority last year, he said he wanted to see more of the watchdog's work opened to public scrutiny. The public had good cause to be optimistic.

As chairman of the Parole Board before his IPCA appointment, Sir David lifted the veil on the agency's operations. As a result, the public knows a lot more about the processes and reasons behind its decisions.

There were high hopes he would engineer a similar culture change at the IPCA. Indeed, he told Radio New Zealand in October he wanted fewer of its reports kept secret: "At the moment, we privately report on a lot of cases, we do that to the [police] commissioner, make recommendations, we follow those up, trying to change practice and policy for the future. We need to expose a bit more of that".

There was certainly a need. The IPCA receives about 2000 complaints a year. Many of those will be frivolous or unfounded, but the fact it produced just 17 public reports in 2010-11 strongly indicates most of its work is secret.

Its refusal to publish the findings of its investigation into the police handling of murder suspect Timothy Parlane is a case in point.

Mr Parlane was hit by a train and killed early on March 5, 2011, just hours after police interviewed him in relation to the murder of Johnsonville man Matthew Hall. The next month, this newspaper reported that a female friend of Mr Parlane said he had confessed to her on March 2 that he was the killer. That confession came after his first interview with police earlier that day.

The woman reported that conversation to police on March 3, and insists she repeatedly told them he had threatened suicide if he was interviewed.

Police questioned him again on March 4, and released him. The woman said a detective told her police could not hold Mr Parlane, but he had been issued with protection and trespass orders relating to her.

The case raises many important questions. Given what the woman says she told police, did those who conducted the second interview with him detect or suspect he might be contemplating drastic action? If so, what did police do to seek help for him? If he could not be kept in custody, what steps were taken after his release to ensure he was safe, and, more importantly, the woman, too?

The public deserves answers to those questions, but all the IPCA will say is that it has investigated the circumstances surrounding Mr Parlane's death and reported the results to his family and Police Commissioner Peter Marshall.

The police are only slightly more forthcoming, revealing they have accepted the IPCA's recommendation that the commissioner review "current policy, modifies it if necessary and develops an appropriate custodial management training programme".

That indicates the IPCA found some fault with the police. If it is not prepared to say what, and how material it was to what transpired, then Sir David should explain why he thinks the public has no right to know.